Population, Consumption & the Environment

Transcription

1 Population, Consumption & the Environment Alex de Sherbinin Center for International Earth Science Information Network (CIESIN), the Earth Institute at Columbia University Population-Environment Research Network 2 1

2 Why is this important? Global GDP is 20 times higher today than it was in 1900, having grown at a rate of 2.7% per annum (population grew at the rate of 13% 1.3% p.a.) CO2 emissions have grown at an annual rate of 3.5% since 1900, reaching 100 million metric tons of carbon in 2001 The ecological footprint, a composite measure of consumption measured in hectares of biologically productive land, grew from 4.5 to 14.1 billion hectares between 1961 and 2003, and it is now 25% more than Earth s biocapacity For CO2 emissions and footprints, the per capita impacts of high income countries are currently 6 to 10 times higher than those in low income countries 3 Outline 1. What kind of consumption is bad for the environment? 2. How are population dynamics and consumption linked? 3. Who is responsible for environmentally damaging consumption? 4. What contributions can demographers make to the understanding of consumption? 5. Conclusion: The challenge of sustainable consumption 4 2

3 Whatkind of consumption is badfor the environment? SECTION 2 5 What kind of consumption is bad? [Consumption is] human transformations of materials and energy. [It] is environmentally important to the extent that it makes materials or energy less available for future use, and through its effects on biophysical systems, threatens human health, welfare, or other things people value. - Stern, 1997 Early focus on wasteful consumption, conspicuous consumption, etc. (Pew GSI, President s Council on SD) Current recognition that all forms of consumption entail some environmental costs Recent focus on production consumption systems, product lifecycles, cradle to grave assessments, material flow analysis, and displaced impacts through trade 6 3

4 Production consumption system Source: Lebel & Lorek, Annual Reviews, Household consumption Three consumption clusters account for nearly 70% of an economy s material extraction and energy consumption, and 90% of land use: 1. Construction & housing 50% of HH energy consumption, but appear to be saturating 2. Food & nutrition 20 30% of HH energy consumption, and largest portion of land use 3. Transport & mobility 20 30% of HH energy consumption; about50% of transportis leisure related, andpercentage is increasing In China there is a transition from food & housing HEIs to transport & housing impacts (Liu et al. 2009) 8 4

5 Energy Energy has been most studied (consistent units, well defined environmental impacts) World consumes the 77 trillion barrels of oil energy equivalent per year Fossil fuel consumption (oil, coal, natural gas) is 66 trillion barrels of oil energy equivalent 9 Energy use impacts: air pollution 50 PPB = 100 ug/m 3 = WHO limit for 8 hour mean Summer

6 Energy use impacts: climate Source: IPCC Fourth Assessment Report (AR4) Working Group I The Physical Science Basis: Frequently Asked Questions. Cambridge University Press. Environmental impacts food sector 10% of energy 90% of energy Source: OECD 2004 In US, food waste has reached 40%! 12 6

7 How are population dynamics and consumption linked? SECTION 2 13 How are population dynamics & consumption linked? Consumption levels tend to increase with: Urbanization Both of which are correlated Income levels with lower fertility Source: The Economist, 31 Oct

8 Household composition & energy use Energy use goes up with education and income Maleheaded households consume moreenergy energy than female headed households In U.S. smallest households are growing at fastest rate due to increased age at marriage, aging & divorce This increases per capita energy use Sources of growth in energy consumption, % inc. in Due to Due to Due to energy consump. (I) = pop. growth (P) change in income (A) change in tech. (T) Developing Countries 6.7% 2.2% 3.0% 1.5% Developed Countries 2.1% 0.7% 2.0% -0.6% Source: Lutz, Demographic Change and Environment, Open Meeting of HDGEC, June

9 Distribution of HH size: U.S. and Mexico Percent of persons in occupied housing unit, by number of persons per unit, US and Mexico percent number of persons per occupied housing unit US Mexico Source: U.S. Census Bureau and INEGI IPAT vs. IHAT: Developed country growth in energy use I = 2.1 PAT HAT Percent Total growth Pop. Affluence & tech. No. of households Affluence & tech. Source: Lutz, Demographic Change and Environment, Open Meeting of HDGEC, June

10 Age Structure China Age Structure: 2000 and Migration & consumption Migration can be motivated by conceptions of the good life Recent migrants to the US generally consume less than other Americans, but within a few generations the gap is closed 20 10

11 Whois responsible for environmentally significant consumption? SECTION 3 21 Who is responsible for consumption? The world s consumer class is disproportionately but not solely in developed countries Theory of consumer sovereignty Yet, marketing stimulates demand The corporate tail wagging the consumer dog Government policy plays a role through taxation, subsidies, investments, etc. Large organizations governments & corporations also consume resources directly for institutional purposes 22 11

12 Source: Curran & de Sherbinin What can demographers contribute to the understanding of consumption patterns and processes? patterns andprocesses? SECTION

13 Role of demographic research Study household processes and their relationship to consumption patterns Size, Composition i (age, sex, income, education), Lifecycles Study different preferences/patterns by age, sex, urban, & rural status Exploit consumer demographic databases to identify levers for change Identify consumption transitions similar to demographic transition Survey research on values : Understanding when and where green values translate into action KAP gap type research: where people express values or desires that are not consistent with their actual behavior 25 Knowledge 13

14 Attitudes Practice 14

15 Conclusions thechallenge of sustainable consumption SECTION 5 29 Required Reductions in Per Capita Gasoline Equivalent Consumption for Climate Stabilization USA Russia China Japan ~100 gallons/ person/year Emission reductions on the order of per cent of 1990-level emissions would be necessary to stabilize concentrations of carbon dioxide in the atmosphere. UNFCCC (2006), 15

16 Challenges (1) Much consumption is locked in Housing stock is only renewed every 50+ years & can be improved only marginally >50% of mobility is between home and work place Political resistance to policies to reduce, regulate or tax consumption so as to internalize externalities The scale effects generally overwhelm improvements in efficiency and technology Directly related to population size and growth 31 Challenges (2) The reduction of population growth had many win win elements but consumption reduction has few politically powerful proponents Values and consumer preferences are hard though not impossible to change Lack of information for even well intentioned consumers Out of sight, out of mind Globalization separates the environmental externalities from the site of consumption Urbanization has reduced contact with nature (biophobia among children in Hong Kong) 32 16

17 Change is hard! Challenges (3) 33 Observations Need to move from normative to normal price signals and consumer options will need to make it normal l to consume less, not a counter culture decision i Not just socialist vs. capitalist models, but also statist, and Other Worlds are Possible (IPCC) We seem to face a number of closely connected processes that reinforce unsustainable patterns of consumption, including individualization, the spread of market values, globalization, urbanization, and the changing nature of risk and our response to it. In some cases, counterforces seem to be emerging the processes may be self limiting. But it is hard to imagine a way in which the forces supporting consumption patterns could be deliberately altered. Businesses and governments seem to be swept up in these grand societal developments. The best they can do is ride the waves. - L. Michaelis, Oxford Commission on Sustainable Consumption 34 17

18 THANK YOU MUCHAS GRACIAS 35 18